<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<title>Title</title>
	<script src="jquery.min.js"></script>

</head>
<body>
<input type="button" name="" value="点击" id="btu">

<script>
	$('input').click(function () {
		alert(2);
	});
</script>

</body>
</html>